Sciatica

Sciatica

Definition

Sciatica refers to pain or discomfort associated with the sciatic nerve. This nerve runs from the lower part of the spinal cord down the back and side of the leg to the foot. Injury to or pressure on the sciatic nerve can cause the characteristic pain of sciatica: a sharp or burning pain or even numbness that radiates from the lower back or hip, possibly following the path of the sciatic nerve to the foot.

Description

The sciatic nerve is the largest and longest nerve in the body. About the thickness of a person's thumb, it spans from the lower back to the foot. The nerve originates in the lower part of the spinal cord, the so-called lumbar region. As the sciatic nerve branches off from the spinal cord, it passes between the bony vertebrae (the component bones of the spine) and runs through the pelvic girdle, or hip bones, and the buttock area. The nerve passes through the hip joint and continues down the back and side of the leg to the foot.

Sciatica is a fairly common disorder, approximately 40% of the population experiences it at some point in their lives. However, only about 1% have coexisting sensory or motor deficits. Sciatic pain has several root causes and treatment may hinge upon the underlying problem.

Of the identifiable causes of sciatic pain, lumbosacral radiculopathy and back strain are the most frequently suspected. The term lumbosacral refers to the lower part of the spine, and radiculopathy describes a problem with the spinal nerve roots that pass between the vertebrae and give rise to the sciatic nerve. This area between the vertebrae is cushioned with a disk of shock-absorbing tissue. If this disk shifts or is damaged through injury or disease, the spinal nerve root may be compressed by the shifted tissue or the vertebrae.

This compression of the nerve roots sends a pain signal to the brain. Although the actual injury is to the nerve roots, the pain may be perceived as coming from any point along the sciatic nerve.

The sciatic nerve can be compressed in other ways. Back strain may cause muscle spasms in the lower back, placing pressure on the sciatic nerve. In rare cases, infection, cancer , bone inflammation, or other diseases may cause the pressure. More likely, but often overlooked, is the piriformis syndrome. As the sciatic nerve passes through the hip joint, it shares the space with several muscles. One of these muscles, the piriformis muscle, is closely associated with the sciatic nerve. In some people, the nerve actually runs through the muscle. If this muscle is injured or has a spasm, it places pressure on the sciatic nerve—in effect, compressing it.

In many sciatica cases, the specific cause is never identified. About half of affected individuals recover from an episode within a month. Some cases can linger a few weeks longer and may require aggressive treatment. In other cases, the pain may return or potentially become chronic.

Causes & symptoms

Persons with sciatica may experience some lower back pain, but the most common symptom is pain that radiates through one buttock and down the back of the adjoining leg. The most identified cause of the pain is compression or pressure on the sciatic nerve. The extent of the pain varies among individuals. Some people describe pain that centers in the area of the hip, and others perceive discomfort all the way to the foot. The quality of the pain also varies; it may be described as tingling, burning, prickly, aching, or stabbing.

Onset of sciatica can be sudden, but it can also develop gradually. The pain may be intermittent or continuous. Certain activities, such as bending, coughing, sneezing , or sitting, may make the pain worse.

Chronic pain may arise from more than just compression on the nerve. According to some pain researchers, physical damage to a nerve is only half of the equation. A recent theory proposes that some nerve injuries result in a release of neurotransmitters and immune system chemicals that enhance and sustain a pain message. Even after the injury has healed or the damage has been repaired, the pain continues. Control of this abnormal type of pain is difficult.

Diagnosis

Before treating sciatic pain, as much information as possible must be collected. The individual is asked to recount the location and nature of the pain, how long it has continued, and any accidents or unusual activities prior to its onset. This information provides clues that may

point to back strain or injury to a specific location. Back pain from disk disease, piriformis syndrome, and back strain must be differentiated from more serious conditions such as cancer or infection. Lumbar stenosis, an overgrowth of the covering layers of the vertebrae that narrows the spinal canal, must also be considered. The possibility that a difference in leg lengths is causing the pain should be evaluated; the problem can be easily be treated with a foot orthotic or built-up shoe.

Often, a straight-leg-raising test is done, in which the person lies face upward and the healthcare provider raises the affected leg to various heights. This test pinpoints the location of the pain and may reveal whether it is caused by a disk problem. Other tests, such as having the individual rotate the hip joint, assess the condition of the hip muscles. Any pain caused by these movements may provide information about involvement of the piriformis muscle, and piriformis weakness is tested with additional leg-strength maneuvers.

Further tests may be done depending on the results of the physical examination and initial pain treatment. Such tests might include magnetic resonance imaging (MRI) and computed tomography (CT) scans. Other tests examine the conduction of electricity through nerve tissues, and include studies of the electrical activity generated as muscles contract (electromyography), nerve conduction velocity, and evoked potential testing. A more invasive test involves injecting a contrast substance into the space between the vertebrae and making x-ray images of the spinal cord (myelography), but this procedure is usually done only if surgery is being considered as an option. All of these tests can reveal problems with the vertebrae, the disk, or the nerve itself.

Treatment

Massage is a recommended form of therapy, especially if the sciatic pain arises from muscle spasm. Symptoms may also be relieved by icing the painful area as soon as the pain occurs. Ice should be left on the area for 30–60 minutes several times a day. After two or three days, a hot water bottle or heating pad can replace the ice. Chiropractic or osteopathy may offer possible solutions for relieving pressure on the sciatic nerve and alleviating the accompanying pain. Biofeedback may also be useful as a pain control method. Bodywork, such as the Alexander technique , can assist an individual in improving posture and preventing further episodes of sciatic pain.

Acupuncture is another alternative approach that appears to offer relief to many persons with sciatica, as indicated by several clinical trials in the United States and Europe. The World Health Organization (WHO) lists sciatica as one of 40 conditions for which acupuncture is recognized as an appropriate complementary treatment.

Practitioners of Ayurvedic medicine regard sciatica as a disorder resulting from an imbalance in vata, one of three doshas or energies in the human body. The traditional Ayurvedic treatment for vata disorders is vasti, or administration of an oil-based enema to cleanse the colon. An Ayurvedic herbal preparation that is used to treat sciatica is made from the leaves of Nyctanthes arbor tristis, which is also known as Parijat or "sad tree." A recent study of an alcohol-based extract of this plant indicates that it is effective as a tranquilizer and local anesthetic, which supports its traditional Ayurvedic use.

Western herbalists typically treat sciatica with valerian root to relax the muscle spasms that often accompany sciatica, and with white willow bark for pain relief.

Homeopathic remedies for sciatica include Ruta graveolens, Colocynth (for sciatic pain that is worse in cold or damp weather), or Magnesium phosphoric (for lightning-like pains that are soothed by heat and made worse by coughing).

Allopathic treatment

Initial treatment for sciatica focuses on pain relief. For acute or very painful flare-ups, bed rest is advised for up to a week in conjunction with medication for the pain. Pain medication includes acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, or muscle relaxants. If the pain is unremitting, opioids may be prescribed for short-term use, or a local anesthetic will be injected directly into the lower back. Massage and heat application may be suggested as adjuncts.

If the pain is chronic, different pain relief medications are used to avoid long-term dosing of NSAIDs, muscle relaxants, and opioids. Antidepressant drugs, which have been shown to be effective in treating pain, may be prescribed alongside short-term use of muscle relaxants or NSAIDs. Local anesthetic injections or epidural steroids are used in selected cases.

As the pain allows, physical therapy is introduced into the treatment regime. Stretching exercises that focus on the lower back, buttock, and hamstring muscles are suggested. The exercises also include finding comfortable, pain-reducing positions. Corsets and braces may be useful in some cases, but evidence for their general effectiveness is lacking. However, they may be helpful to prevent exacerbations related to certain activities.

With less pain and the success of early therapy, the individual is encouraged to follow a long-term program to maintain a healthy back and prevent re-injury. A physical therapist may suggest exercises and regular activity, such as water exercise or walking. Patients are instructed in proper body mechanics to minimize symptoms during light lifting or other activities.

If the pain is chronic and conservative treatment fails, surgery to repair a herniated disk or to cut out part or all of the piriformis muscle may be suggested, particularly if there is evidence of nerve or nerve-root damage.

A new minimally invasive surgical treatment for sciatica was introduced in 2002. It is known as microscopically assisted percutaneous nucleotomy, or MAPN. MAPN allows the surgeon to repair a herniated disk with less damage to surrounding tissues; it shortens the patient's recovery time and relieves the pain of sciatica as effectively as more invasive surgical procedures.

Expected results

Most cases of sciatica are treatable with pain medication and physical therapy. After four to six weeks of treatment, an individual should be able to resume normal activities.

Prevention

Some sources of sciatica are not preventable, such as disk degeneration, back strain due to pregnancy , or accidental falls. Other sources of back strain, such as poor posture, overexertion, being overweight, or wearing high heels, can be corrected or avoided. Cigarette smoking may also predispose people to pain, and should be discontinued with the onset of pain.

General suggestions for avoiding sciatica or preventing a repeat episode include sleeping on a firm mattress; using chairs with firm back support; and sitting with both feet flat on the floor. Habitually crossing the legs while sitting can place excess pressure on the sciatic nerve. Sitting for long periods of time can also place pressure on the sciatic nerves, so it is recommended to take short breaks and move around during the work day, during long trips, or in other situations that require sitting for extended periods of time. If lifting is required, the back should be kept straight and the legs should provide the lift. Regular exercise, such as swimming and walking, can strengthen back muscles and improve posture. Exercise can also help maintain a healthy weight and lessen the likelihood of back strain.

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Sciatica

Gale Encyclopedia of Medicine, 3rd ed.
COPYRIGHT 2006 Thomson Gale

Sciatica

Definition

Sciatica refers to pain or discomfort associated with the sciatic nerve. This nerve runs from the lower part of the spinal cord, down the back of the leg, to the foot. Injury to or pressure on the sciatic nerve can cause the characteristic pain of sciatica: a sharp or burning pain that radiates from the lower back or hip, possibly following the path of the sciatic nerve to the foot.

Description

The sciatic nerve is the largest and longest nerve in the body. About the thickness of a person's thumb, it spans from the lower back to the foot. The nerve originates in the lower part of the spinal cord, the so-called lumbar region. As it branches off from the spinal cord, it passes between the bony vertebrae (the component bones of the spine) and runs through the pelvic girdle, or hip bones. The nerve passes through the hip joint and continues down the back of the leg to the foot.

Sciatica is a fairly common disorder and approximately 40% of the population experiences it at some point in their lives. However, only about 1% have coexisting sensory or motor deficits. Sciatic pain has several root causes and treatment may hinge upon the underlying problem.

Of the identifiable causes of sciatic pain, lumbosacral radiculopathy and back strain are the most frequently suspected. The term lumbosacral refers to the lower part of the spine, and radiculopathy describes a problem with the spinal nerve roots that pass between the vertebrae and give rise to the sciatic nerve. This area between the vertebrae is cushioned with a disk of shockabsorbing tissue. If this disk shifts or is damaged through injury or disease, the spinal nerve root may be compressed by the shifted tissue or the vertebrae.

This compression of the nerve roots sends a pain signal to the brain. Although the actual injury is to the nerve roots, the pain may be perceived as coming from anywhere along the sciatic nerve.

The sciatic nerve can be compressed in other ways. Back strain may cause muscle spasms in the lower back, placing pressure on the sciatic nerve. In rare cases, infection, cancer, bone inflammation, or other diseases may be causing the pressure. More likely, but often overlooked, is the piriformis syndrome. As the sciatic nerve passes through the hip joint, it shares the space with several muscles. One of these muscles, the piriformis muscle, is closely associated with the sciatic nerve. In some people, the nerve actually runs through the muscle. If this muscle is injured or has a spasm, it places pressure on the sciatic nerve, in effect, compressing it.

In many sciatica cases, the specific cause is never identified. About half of affected individuals recover from an episode within a month. Some cases can linger a few weeks longer and may require aggressive treatment. In some cases, the pain may return or potentially become chronic.

Causes and symptoms

Individuals with sciatica may experience some lower back pain, but the most common symptom is pain that radiates through one buttock and down the back of that leg. The most identified cause of the pain is compression or pressure on the sciatic nerve. The extent of the pain varies between individuals. Some people describe pain that centers in the area of the hip, and others perceive discomfort all the way to the foot. The quality of the pain also varies; it may be described as tingling, burning, prickly, aching, or stabbing.

Onset of sciatica can be sudden, but it can also develop gradually. The pain may be intermittent or continuous, and certain activities, such as bending, coughing, sneezing, or sitting, may make the pain worse.

Chronic pain may arise from more than just compression on the nerve. According to some pain researchers, physical damage to a nerve is only half of the equation. A developing theory proposes that some nerve injuries result in a release of neurotransmitters and immune system chemicals that enhance and sustain a pain message. Even after the injury has healed, or the damage has been repaired, the pain continues. Control of this abnormal type of pain is difficult.

Diagnosis

Before treating sciatic pain, as much information as possible is collected. The individual is asked to recount the location and nature of the pain, how long it has continued, and any accidents or unusual activities prior to its onset. This information provides clues that may point to back strain or injury to a specific location. Back pain from disk disease, piriformis syndrome, and back strain must be differentiated from more serious conditions such as cancer or infection. Lumbar stenosis, an overgrowth of the covering layers of the vertebrae that narrows the spinal canal, must also be considered. The possibility that a difference in leg lengths is causing the pain should be evaluated; the problem can be easily be treated with a foot orthotic or built-up shoe.

Often, a straight-leg-raising test is done, in which the person lies face upward and the health-care provider raises the affected leg to various heights. This test pinpoints the location of the pain and may reveal whether it is caused by a disk problem. Other tests, such as having the individual rotate the hip joint, assess the hip muscles. Any pain caused by these movements may provide information about involvement of the piriformis muscle, and piriformis weakness is tested with additional leg-strength maneuvers.

Further tests may be done depending on the results of the physical examination and initial pain treatment. Such tests might include magnetic resonance imaging (MRI) and computed tomography scans (CT scans). Other tests examine the conduction of electricity through nerve tissues, and include studies of the electrical activity generated as muscles contract (electromyography ), nerve conduction velocity, and evoked potential testing. A more invasive test involves injecting a contrast substance into the space between the vertebrae and making x-ray images of the spinal cord (myelography ), but this procedure is usually done only if surgery is being considered. All of these tests can reveal problems with the vertebrae, the disk, or the nerve itself.

Treatment

Initial treatment for sciatica focuses on pain relief. For acute or very painful flare-ups, bed rest is advised for up to a week in conjunction with medication for the pain. Pain medication includes acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, or muscle relaxants. If the pain is unremitting, opioids may be prescribed for short-term use or a local anesthetic will be injected directly into the lower back. Massage and heat application may be suggested as adjuncts.

If the pain is chronic, different pain relief medications are used to avoid long-term dosing of NSAIDs, muscle relaxants, and opioids. Antidepressant drugs, which have been shown to be effective in treating pain, may be prescribed alongside short-term use of muscle relaxants or NSAIDs. Local anesthetic injections or epidural steroids are used in selected cases.

As the pain allows, physical therapy is introduced into the treatment regime. Stretching exercises that focus on the lower back, buttock, and hamstring muscles are suggested. The exercises also include finding comfortable, pain-reducing positions. Corsets and braces may be useful in some cases, but evidence for their general effectiveness is lacking. However, they may be helpful to prevent exacerbations related to certain activities.

With less pain and the success of early therapy, the individual is encouraged to follow a long-term program to maintain a healthy back and prevent re-injury. A physical therapist may suggest exercises and regular activity, such as water exercise or walking. Patients are instructed in proper body mechanics to minimize symptoms during light lifting or other activities.

If the pain is chronic and conservative treatment fails, surgery to repair a herniated disk or cut out part or all of the piriformis muscle may be suggested, particularly if there is neurologic evidence of nerve or nerve-root damage.

Alternative treatment

Massage is a recommended form of therapy, especially if the sciatic pain arises from muscle spasm. Symptoms may also be relieved by icing the painful area as soon as the pain occurs. Ice should be left on the area for 30-60 minutes several times a day. After 2-3 days, a hot water bottle or heating pad can replace the ice. Chiropractic or osteopathy may offer possible solutions for relieving pressure on the sciatic nerve and the accompanying pain. Acupuncture and biofeedback may also be useful as pain control methods. Body work, such as the Alexander technique, can assist an individual in improving posture and preventing further episodes of sciatic pain.

Prognosis

Most cases of sciatica are treatable with pain medication and physical therapy. After 4-6 weeks of treatment, an individual should be able to resume normal activities.

Prevention

Some sources of sciatica are not preventable, such as disk degeneration, back strain due to pregnancy, or accidental falls. Other sources of back strain, such as poor posture, overexertion, being overweight, or wearing high heels, can be corrected or avoided. Cigarette smoking may also predispose people to pain, and should be discontinued.

General suggestions for avoiding sciatica, or preventing a repeat episode, include sleeping on a firm mattress, using chairs with firm back support, and sitting with both feet flat on the floor. Habitually crossing the legs while sitting can place excess pressure on the sciatic nerve. Sitting a lot can also place pressure on the sciatic nerves, so it's a good idea to take short breaks and move around during the work day, long trips, or any other situation that requires sitting for an extended length of time. If lifting is required, the back should be kept straight and the legs should provide the lift. Regular exercise, such as swimming and walking, can strengthen back muscles and improve posture. Exercise can also help maintain a healthy weight and lessen the likelihood of back strain.

Citation styles

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Sciatica

Sciatica

Definition

Sciatica is pain in the lower back that can radiate down the buttocks and leg and occasionally into the foot. The pain is a result of inflammation of the sciatic nerve, usually from a herniated vertebral disk, although other causes are common. Sciatica is one of the frequently reported causes of lower back pain .

Description

Sciatica, also known as lumbago or lumbar radiculopathy , causes pain as a result of pressure on the sciatic nerve. The sciatic nerve is formed from lumbar roots that emerge from the spinal column. It rises into the pelvis, and travels down the buttocks, the leg, and into the foot. Occurring on both the left and right side of the body, these nerves are the largest in the body, with a diameter as great as a finger; they branch at several points along their path. Sciatica occurs when these nerves become irritated, most often because of a herniated vertebral disk that puts pressure on the sciatic nerve as it emerges from the spinal column.

Sciatica causes pain that may be constant or intermittent and it may include numbness, burning, or tingling. Coughing, sneezing, bending over, or lifting heavy objects may increase the pain. In some cases, there is weakening of muscles in the buttocks, legs, and/or feet.

Demographics

Sciatica is one of the most common forms of back pain. It occurs in about 5% of people who visit their doctor for back pain and in 1–3% of the general adult population. It is most common in people who are between 30 and 50 years of age, as those are the ages most prone to herniating vertebral disks. After age 30, the tough exterior of the vertebral disks undergoes a natural thinning, making it easier for the gel-like inner core to rupture it. After the age of 50, the interior of the vertebral disk becomes slightly hardened, making it less likely to protrude out.

Causes and symptoms

Pressure on the sciatic nerve can result from poor posture, muscle strain, pregnancy, wearing high heels, or being overweight. A herniated disk in the lumbar spine is the most common cause of sciatica. Herniated disks occur when the gel-like inner core of a vertebral disk (nucleus puposus ) ruptures through the tougher outer section (annulus ) of the disk. This extrusion puts pressure on the nerve root, causing it to function improperly. Another common cause of sciatica is lumbar spinal stenosis, or narrowing of the spinal canal, which puts pressure on the roots making up the sciatic nerve. Degenerative disk disease causes sciatica when the disk weakens enough to allow excessive movement of the vertebrae near the sciatic nerve. In addition, the degenerated disk may leak irritating proteins in the vicinity of the nerve. Although isthmic spondylolisthesis is relatively common in adults, it only occasionally causes sciatica. This occurs when a vertebra develops a stress fracture and slips, slightly impinging on the sciatic nerve as it exits the spine. Piriformis syndrome causes sciatica when the sciatic muscle is irritated as it runs under the piriformis muscle in the buttocks. Finally, sacroiliac joint dysfunction can put pressure on the sciatic nerve, leading to sciatica.

Diagnosis

A physician will perform a physical exam on a patient complaining of sciatica in order to try to identify the part of the nerve that is irritated. This exam may include squatting, walking, standing on toes, and leg raising tests. Most commonly, lifting the leg to a 45° angle while holding it straight helps localize the pain. Other tests that may be performed include x ray to look for stress fractures in bones and magnetic resonance imaging (MRI) or computerized tomography (CT ) to look at softer tissues and ligaments. A nerve conduction velocity test and electromyography may also aid in diagnosis.

Treatment

In most cases, conservative treatments are effective for sciatica. A short period of rest, coupled with the application of cold packs and heat packs to the affected area, reduces inflammation of the nerve. Non-steroidal anti-inflammatory medicines can also be taken to decrease inflammation. Injection of corticosteriods may also be recommended to decrease swelling of the nerve. Physical therapy and short walks are also recommended.

If after three or more months, sciatica continues and become progressively worse, surgical techniques can be used to relieve the pressure on the sciatic nerve. Surgery is often very effective in relieving pain, although results can vary depending upon the cause of the sciatica. Overall, about 90% of patients undergoing surgery for sciatica pain receive some relief.

Recovery and rehabilitation

Usually, sciatica improves within a few weeks. In cases of severe injury to the nerve, such as laceration or other trauma, recovery may be not possible or may be limited. The extent of disability may vary from partial to complete loss of movement or sensation in the affected leg. Nerve pain may also persist.

Clinical trials

A recent drug trial found that the drug Remicade (infliximab), which is used to treat arthritis, is often effective for treating sciatica. The drug reduces the level of a chemical called tumor necrosis factor alpha, which plays an important role in the inflammatory response of the body. It is thought that this factor is also critical to sciatica.

The National Institutes of Health (NIH) are conducting three ongoing studies on the treatment of sciatica. One study investigates the effects of the antidepressants desipramine and benztropine on sciatica. A second looks at the effects of magnets on sciatica. A third investigates the role of two drugs, nortriptyline and MS Contin (a type of morphine), as treatment for sciatica. Contact information for these studies is the National Institute for Dental and Craniofacial Research (NIDCR), 9000 Rockville Pike, Bethesda, MD 20892; the toll-free number is (800) 411-1222.

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When something squeezes the sciatic nerve, the main nerve in the leg, people feel pain in the back of the lower body. That pain, called sciatica,
usually moves down the buttocks to the leg below the knee, but it can go all the way down to the foot. Sciatica varies from mild, tingling pain to severe pain that leaves people unable to move. Some people with sciatica feel sharp pain in one part of the leg or hip and numbness in other parts. This pain gets worse after standing or sitting for a long time.

Sciatica is most common in people who are ages 30 to 70, and it affects about three times as many men as women. At risk are:

There are many ways the sciatic nerve can become compressed, but the exact cause is often unknown. The most common causes of sciatica are a herniated disc or a tumor within the spine. Discs are the pads between the bones (called vertebrae) of the spine. They are filled with a gelatin-like substance that cushions the vertebrae from the impact of walking, running, lifting, and similar activities.

A disc that has torn and has this gelatin-like material oozing out of it is said to be herniated. Other common causes of sciatica include bony irregularities of the vertebrae such as osteoarthritis* or spondylolisthesis*. Spinal stenosis* is a less common cause. In some cases, diabetes or alcoholism can cause sciatica.

Sciatica is diagnosed through a medical history and a physical examination. Sciatica often clears up within several days to a week. It is usually treated with bed rest for a day or two (only if people cannot bear the pain), local heat, massage, pain relievers, and muscle relaxants. Sciatica tends to return and can become chronic*. Chronic sciatica is treated by trying to alleviate the cause of the pain by advising people to lose weight, improve muscle tone and strength, and improve posture. Surgery may be necessary in cases where there is no relief from pain, disc disease, or spinal stenosis. The goal of surgery is to eliminate the source of pressure on the sciatic nerve.

Sciatica or recurrence of sciatica can sometimes be prevented by standing, sitting, and lifting properly; exercising; and working in a safe environment. That means using chairs, desks, and equipment that support the back or help maintain good posture, and taking precautions when lifting and bending.

Book

Organization

National Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health. Office of Communications and Public Liaison, Building 31,Room 7A-50, 31 Center Drive, MSC 2520, Bethesda, MD 20892-2520. Consumer health information is available on its website. Telephone 301-496-4000 http://www.nih.gov

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sciatica

The Columbia Encyclopedia, 6th ed.

Copyright The Columbia University Press

sciatica (sīăt´Ĭkə), severe pain in the leg along the sciatic nerve and its branches. It may be caused by injury or pressure to the base of the nerve in the lower back, or by metabolic, toxic, or infectious disease. Treatment is for the underlying condition; measures for the relief of pain include bed rest, immobilization of the leg, heat, and sedation.

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sciatica

sciatica (sy-at-ik-ă) n. pain felt down the back and outer side of the thigh, leg, and foot. It is usually caused by degeneration or tearing of an intervertebral disc, which protrudes laterally to compress a spinal nerve root. The onset may be sudden, brought on by an awkward lifting or twisting movement.

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sciatica

sci·at·i·ca
/ sīˈatikə/
•
n.
pain affecting the back, hip, and outer side of the leg, caused by compression of a spinal nerve root in the lower back, often owing to degeneration of an intervertebral disk.

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sciatica

sciatica Severe pain in the back and radiating down one or other leg, along the course of the sciatic nerve. It is usually caused by inflammation of the sciatic nerve or by pressure on the spinal nerve roots.

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